The anticancer drug cisplatin binds to duplex DNA at the N7 atoms of adjacent purine nucleotides to form a diammineplatinum 1,2-intrastrand crosslink. This adduct causes structural deformation in the duplex including bending of the helix at the site of platination and unwinding of helix resulting in a widened and flatten minor groove. HMG domain proteins recognize the damaged DNA and bind to the helix in the widened minor groove. We have begun a study of complexes of 15 N-labeled HMG1 domain A and HMG1 domain B with a site-specifically platinated 15-mer duplex DNA. Preliminary 2D 'H-H NOESY, 2D 'H- 15 N HSQC, and 3D 'H- 15 N HSQC-'H-'H NOESY spectra have been collected at 500 and 750 MHz on custom built instruments at FBML. Studies are ongoing to examine these preliminary spectra and determine whether this complex or others can be used for solution structure determination of a HMG1 domain-Pt-DNA complex by NMR.